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"SMALL CAR MODELS DIFFERENTIAL DRAIN PLUG
Novemder 1, 1963
The rear differential case drain plug has been deleted from production on the Herald, Spitfire and Sport Six.
In future service requirements for the differential are reduced to topping up to correct level. Draining and refilling will not be necessary.
Drain plugs will be retained in gearboxes for this models but service requirements will be reduced to topping up up rather than drain and refill.
Future maintenance instructions will be suitably amened."
mfG
Harry